Alas, what it taught people was to describe others who want to help them ask better questions as "gatekeepers".

Maybe SO really is full of rude, condescending gatekeepers - I haven't asked questions there much.

I haven't personally seen much evidence of it, though, despite decades of winding up there when searching for programming information.

If you haven’t asked questions how would you know? A question that gets incorrectly closed as a duplicate would never get seen by you.

Perception is reality.

If everyone thinks their question will get closed, it might as well be reality because no one is going to ask and they are going to go elsewhere. Which is exactly what happened.